1. Technical Field of the Invention
The present invention relates to a liquid container that contains a liquid to be supplied to a liquid jetting apparatus therein.
2. Description of the Related Art
As a liquid container that contains a liquid to be used in a liquid jetting apparatus, for example, an ink cartridge that is used in an ink jet printer can be exemplified. The ink cartridge for an ink jet printer has an ink containing chamber that is provided in a container main body and contains ink to be supplied to a printing head. Upon use, the ink cartridge is detachably fitted into and mounted on a cartridge mounting portion located at a predetermined position. Then, ink contained in the ink containing chamber is supplied to the printing head that is driven according to printing data to be transmitted from a host computer, and then is jetted to a target position on a subject to be printed, such as a paper or the like, by nozzles provided in the printing head.
In general, the ink jet printer has a carriage, on which the printing head ejecting ink droplets is mounted and which reciprocates in a direction perpendicular to a feed direction of the subject to be printed. Further, as a method of supplying ink from the ink cartridge to the printing head, a method of mounting the ink cartridge on the cartridge mounting portion provided in the carriage and supplying ink from the ink cartridge reciprocating along with the printing head to the printing head (a so-called on-carriage type) is used. Further, as another method, a method of mounting the ink cartridge on the cartridge mounting portion provided at a place other than the carriage of the ink jet printer and supplying ink from the ink cartridge to the printing head through an ink flow passage formed of a flexible tube (a so-called off-carriage type) is used.
As the ink cartridges that are mounted on the off-carriage type ink jet printers, various configurations including the configuration disclosed in JP-A-2002-19135 have been suggested.
An ink cartridge 201 shown in FIG. 11 is one disclosed in JP-A-2002-19135. In the ink cartridge 201, an ink containing chamber 209 whose volume is reducible by a pressure due to pressurized air to be supplied to a pressure chamber 207 in a container main body 205 is formed in the container main body 205 that is mounted on a cartridge mounting portion 203 of an ink jet printer. An ink liquid to be used in the ink jet printer is contained in the ink containing chamber 209. Two positioning portions 213 that fit to positioning units 211 provided at two places in the cartridge mounting portion 203 so as to position the container main body 205, an ink delivery port 217 that connects an ink supply path (an ink supply needle) 215 of the cartridge mounting portion 203 to the ink containing chamber 209, a pressurized air introduction portion 221 that connects a pressurized air supply path 219 of the cartridge mounting portion 203 to the pressure chamber 207, and a data storage unit 225 that is connected to a connection terminal 223 of the cartridge mounting portion 203 are provided at one surface (front end surface) of the container main body 205
The data storage unit 225 is a memory device that readably/writably stores various kinds of data, such as the kind of the ink cartridge 201 or consumption history of ink, from a control unit of the ink jet printer. As for the data storage unit 225, accurate positioning is needed such that an inconsistency, such as a defective operation due to contact failures of contacts to the connection terminal 223 of the cartridge mounting portion 203, is not caused.
Accordingly, in the ink cartridge 201, the positioning portions 213 are disposed immediately inside the pressurized air introduction portion 221 and the data storage unit 225 disposed at both ends of one surface of the cartridge main body 205 so as to be close to them, respectively.
The ink containing chamber of the ink cartridge desirably has a large ink containing capacity. However, as shown in FIGS. 11 and 12, in the structure in which all connection mechanisms disposed in the vicinity of the ink delivery port, such as the pressurized air introduction portion 221, the two positioning portions 213, the ink delivery port 217, the data storage unit 225, and so on, are substantially disposed in a line, the connection mechanisms occupy the front surface of the ink cartridge, and thus the external shape of the ink cartridge is made large with respect to the ink capacity so much. Further, in the cartridge mounting portion, the parts corresponding to the connection mechanisms are provided, and thus the ink cartridge is likely to be large in size.
In the configuration shown in FIG. 11, the interval P1 between the two positioning portions 213 is drastically made narrow compared with the width W1 of the container main body 205. Accordingly, when a torsional load indicated by arrows A and B in FIG. 12 is applied, displacement or deformation at both widthwise ends of the container main body 205 is insufficiently suppressed. Then, positioning accuracy of the data storage unit 225 may be degraded due to the displacement or deformation at both widthwise ends of the container main body 205, and the defective operation of the data storage unit 225 may be caused due to the contact failures of the contacts.
Displacement or deformation at both widthwise ends of the container main body may be caused due to a pressure by pressurized air to be supplied to the pressure chamber. In this case, positioning accuracy to the cartridge mounting portion may also be degraded.